


A Friend In Need

by MageOfLight



Series: i swear, this was supposed to just be poly skeleheat sin. now there's an extended story. huh. [5]
Category: Undertale
Genre: Blueberry generally wrecking Red, Cherryberry - Freeform, Consensual Somnophilia, Eye socket fucking, M/M, Monster Heat, Over stimulation, Panic Attack, Psudo sub heat, Skeleheat, dom heat
Language: English
Status: Completed
Published: 2016-12-19
Updated: 2017-03-25
Packaged: 2018-09-09 18:57:33
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 9,448
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8908162
Author URL: https://archiveofourown.org/users/MageOfLight/pseuds/MageOfLight
Summary: US!Papyrus heads off for a week-long science convention with Undyne. Unfortunately, US!Sans goes into heat without Papy there to head it off before it sets in. UF!Sans decides to help the blueberry out.





	1. Chapter 1

**Notes for the Chapter:**

> thank you, Amashi_zaino for the name. it's perf. :)

"Have fun, Papy! See you in a week!" Blue called, waving as Papyrus slid into Undyne's car. Papyrus waved back, grinning, then shut the door. Blue could see Papyrus engaging in animated conversation with Undyne as the car started to pull away. Once they were gone, however, the small skeleton sagged slightly.  
  
He was now alone in the house. Papyrus was headed off to some week-long science convention, and Red was still at work, making up for lost hours from the two days he'd spent in heat and the fourth he'd spent recovering from those three days. He sighed, flopping onto the couch with a groan. He wasn't used to being alone like this.  
  
The rest of the day was spent watching TV, cleaning, or cooking, all in an attempt to distract himself from how utterly alone he was at that point in time. By the time he was ready to go to bed, he firmly decided that he hated being on his own.

\--------------------------------------------

Red sighed as he finished cleaning the final table. There'd been a huge fight between two human customers a couple hours earlier, and it had taken both him and Grillby to pull the two apart and keep them separated until the police could get there. And then there'd been the clean up after that. They'd made a huge mess of the bar, food, drink, and blood splattered everywhere. The gold-toothed skeleton was utterly exhausted now, trembling slightly as he tried not to think of how the vicious fight had reminded him of his original universe.  
  
"Red?" Grillby's calm, quiet voice drew him properly from his thoughts, a warm hand on his shoulder easing his nerves at the same time. "Thank you for staying and helping me get this mess cleaned up. I can finish the rest on my own tonight. Go home and get some rest, my friend," Grillby told him, smiling gently.  
  
Red smiled back gratefully. "okay. thanks, grillbz," he replied, then picked up his mop and bucket, taking them to the back to get rid of the filthy water and put them away. Once he was done that, he changed back into his regular clothing and carefully hung up his work clothing before heading back out into the bar. "see ya tomorrow, grillbz," he called, grinning.  
  
Grillby blinked at him. "But you don't work tomorrow," he said, looking confused. "In fact, you actually have the next two days off," he added after mentally checking the schedule he'd written.  
  
"yeah, i know. doesn't stop me from coming in ta see my friend and enjoy a good burg, does it?" Red replied with a playful wink. Grillby laughed, then waved him off. Red took the hint, yawning as he left the bar. It was past 2:30 am now, and all he wanted to do was go crash in bed for a few hours. He gathered his magic, then stepped into a shortcut, coming out the other side in the middle of the living room.  
  
The house was nearly completely dark, the only light that of the streetlights outside spilling in through the slightly open curtains. Red yawned again, sighing as he trudged upstairs, exhaustion starting to weigh heavily on his bones. Once he got to his room, he stumbled inside, hastily stripped, then fell into bed without bothering to even pull a sleep shirt on. He was too tired, and even if Blue burst into his room in the morning to wake him up, it wasn't like he'd be seeing anything he hadn't seen before.  
  
Sighing, he curled up under his covers and quickly dozed off.

\--------------------------------------------

Surprisingly, Red found himself waking to a pesky beam of sunlight to the face instead of Blue's knocking and morning yelling. He fumbled for his phone a moment, then looked bleary-eyed at the display. 10:47 am was the time that met his gaze and he blinked, staring. That couldn't be right. Blue _always_ woke him before 9 am, even when he knew Red had worked a closing shift. Frowning, Red pulled himself out of bed and got dressed before leaving his room. The house was dead silent. Double weird. He knew Blue had the day off today... in fact, they'd had some loosely cobbled together plans to hang out that day.  
  
Sighing, he headed to Blue's room and raised his hand to knock, only to pause as he heard something inside the room. Holding his breath, he listened. There. What _was_ that...? Furrowing his brow, Red knocked.  
  
No answer. He knocked again. "blue? ya okay?" he called through the door.  
  
"...go away!" Blue called back, sounding frantic. What the... His voice was strangely rough, almost husky sounding and Red felt a pleasant shiver go down his spine. Still worried despite that, he twisted the knob and started opening the door. Blue's reaction was instant, charging the door and slamming it shut. Red shivered, catching a whiff of a powerful sweet scent as the door slammed in his face. It'd smelled kind of like fresh berries, but he didn't even register that fact, his magic having reacted almost violently, pooling in his pelvis and flushing his joints.  
  
...fuck, Blue was in heat, wasn't he? And not a regular heat either, for Red's magic to have reacted like that at such a brief exposure. Of course, Red had done his research after his own heat had ended, using the recovery day to learn as much as he could. Papyrus and Blue had only told him what he'd needed to know to make an informed choice on what he'd been going through, after all.  
  
Sighing, he leaned against the railing across from Blue's door, trying to ignore his burning magic to think. _'okay... so blue's in a dom heat... might be from papyrus constantly heading off his heat before it sinks in? or maybe he does that because blue goes into dom heats? but pap isn't here to help... can i take this on by myself?'_ he shuddered slightly, staring at Blue's door for a moment longer before deciding to go get something to eat. He had a funny feeling he was going to need to be in peak condition for this. He couldn't let the little blueberry suffer through this on his own, after all. Everything he'd read said that dom heats were incredibly difficult, if not impossible to get through alone, and it wasn't like he could call Pap back. Blue would probably kill him for wrecking Papyrus' week, even if he didn't feel horrible for it himself.  
  
As he made himself a late breakfast (consisting of leftovers and food from Muffet's), he pulled out his phone to text Grillby.  
  
*heya, grillbz. won't be coming in today fer lunch after all.  
  
**Oh?  
  
*yeah... uh... might need ta ask ya ta give my hours ta that little part-timer fer a few days, too. something came up, and i don't know how long it's gonna take ta deal with it, or what kind of shape i'll be in after.  
  
**Someone else has gone into heat in the house?  
  
Red flushed as he read that text a couple times.  
  
*...how'd...  
  
**I wasn't going to bring it up, but it was fairly obvious what was going on when you called about being 'sick'.  
  
Red groaned weakly, flopping into a kitchen chair.  
  
*yer an ass. why're we friends?  
  
When no reply came, Red just _knew_ that Grillby was too busy laughing at him to reply.  
  
*anyway, yes. one of my roommates is in heat, and the other one isn't around ta help. dom heat, ta make it worse.  
  
**Ah. Well, that certainly explains why you asked for me to pass your hours on.  
  
there was a pause, and Red assumed Grillby was looking at the schedule and his short list of part-timers.  
  
**I'll give you the week off. That should give you enough time to help out your roommate and recover in the aftermath.  
  
**...and Red? Be careful. Please look after yourself.  
  
*yeah, i will. thanks, grillbz. yer the best.  
  
**I'll drop off a burger and fries for you later.  
  
*oh man, ya really are the best. i have the worst feeling that i'm gonna need it. i'll leave the door unlocked, so if ya don't mind hearing... uh... yeah... ya can just drop it off in the kitchen.  
  
**Got it. Talk to you later, Red.  
  
*later.  
  
Red grinned nervously and pocketed his phone before finishing eating. Once he was done, he washed his dishes off, then plated out some food for Blue. Stars knew he probably hadn't even left his room this morning. Once he was done with that, he tromped upstairs with the plate and a glass of spider cider and knocked on Blue's door. "blue? i'm leaving some food out here fer ya. ya should really eat."  
  
There was a thump on the door as he set the food and drink down. "...thanks," Blue replied a moment later. Red made a show of loudly making his way back to his room, opening and closing his door. Once inside, he stripped down, figuring he'd make it easier on his counterpart. He heard Blue's door open with a creak, then a couple moments later, it closed. He then set in to wait, pulling on a bathrobe before heading downstairs again.  
  
While waiting for Blue to eat, he set about gathering water bottles and snacks, not knowing how long he'd be stuck once he set in to helping Blue out. He could only hope Blue would have enough control to stop if something set him off.  
  
A little bit later, he heard Blue's door open and shut again and he quietly made his way back upstairs. The plate and glass, now empty, sat outside Blue's door and he nodded to himself. "...welp, time ta get this show on the road," he muttered, then gathered his magic and shortcutted into Blue's room.  
  
It was like getting hit with a train to the face. Instantly, Red's magic formed a dripping entrance, and he bit back a groan, dropping his collection of supplies down on the desk before looking at Blue. The skeleton was practically glowing with cyan magic, completely naked and palming his cock, even as he stared wide-eyed at Red. "R-Red? W-what are you doing in here?" he squeaked, looking like he was barely restraining himself from lunging at the practically defenceless skeleton.  
  
Red gulped, fiddling with the fuzzy hems of his robe's sleeves. "i'm here ta help. i can't just... leave ya on yer own like this," he replied, voice shaking slightly with nerves and growing arousal. Stars, but Blue's scent was really starting to get to him.  
  
As if those words snapped Blue's fragile control, the smaller skeleton growled and pretty much pounced at Red, knocking him back onto the bed even as he pressed in to kiss him, tongue coming out to lap at Red's teeth. Red moaned in response, opening his mouth and letting Blue in. The contact of tongue against tongue sent sparks of pleasure shooting down Red's spine, and he groaned lowly, fumbling to untie the belt of his robe. Once he got it, Blue's hands were pushing the robe off his shoulders, palming roughly at his shoulders and clavicles, making Red cry out into the kiss and arch into him.  
  
Blue growled again and ground his erection into Red's mound, letting out a pleased sound as his dick slid against the wet entrance and making Red mewl. The kiss broke as Blue pulled back to get a look at what he'd been given to work with, and he let out another pleased sound as he reached down to finger Red.  
  
"ah! blue!" Red cried out, pressing into Blue's touch. "please, blue... fuck me," he groaned as Blue slid his fingers into Red's cunt. Blue seemed to have lost his words as he simply growled, pulling his fingers out and replacing them with his dick. He barely gave Red a chance to nod before thrusting in, hard and fast. Red nearly screamed, arching his back and pressing into Blue's hips. "ah, fuck! blue, please, oh stars!"  
  
Blue grinned, leaning in to kiss Red again as he set up a punishing pace, thrusting hard and fast into Red's tight warmth, groaning into his mouth. All the gold-toothed skeleton could do was hold on, gasping and crying out as their tongues tangled in his mouth.  
  
All things considered, it didn't take long for Blue to reach his peak, thrusting hard once, twice, three times before stilling deep inside Red and cumming hard. He felt Red's magic accept his and groaned before starting to thrust again, nowhere near finished.  
  
Red, who'd cum moments after Blue did, gasped harshly as Blue resumed movement. Tears gathered in the corners of his eye sockets as he desperately latched on, phalanges wrapping tightly around Blue's ribs in an attempt to ground himself as he pushed back against Blue despite (or perhaps in spite of) the over-stimulation.  
  
Blue's mouth left his, trailing down to lick and nip at his vertebrae, and Red arched his head back, gasping and crying out as Blue continued to relentlessly fuck him hard into the bed. This time, he barely paused when cumming, even as Red squeezed around him. Instead, he grabbed one of Red's femurs, lifting it to change the angle of his thrusts. Red screamed, spine arching hard as the new angle hit an exceptionally sensitive spot, forcing him to fall off the edge a third time with no build up.  
  
"too much, too much, stars, blue, i can't," Red whimpered, thrashing weakly as Blue continued fucking him. It was as if he hadn't heard him though, as Blue just kept moving, wrenching another orgasm from him and cumming a third time himself before finally falling still, panting harshly as his magic pumped into Red and was absorbed.  
  
After a couple minutes, Blue pulled back, withdrawing from Red and pulling a whimper and weak spasm from the slightly taller skeleton before flopping over next to him. His heat seemed to have died down a little as he looked at Red with concern. "Are you... okay? I didn't hurt you, did I?" he asked slowly.  
  
For a moment, Red was unable to reply, but then he let out a breathy laugh. "nah, 'm fine. that was just... a lot more intense than i was expectin'," he murmured tiredly, slurring his words slightly. Boy, was he ever glad he'd eaten before coming in here. "was good, though."  
  
Blue shifted slightly, uncomfortably. "Er... maybe you should go? My heat isn't anywhere close to over, and I-" He was cut off as Red weakly slapped a hand over his mouth.  
  
"shut it. if ya really don't want me here, i'll go. but if the only reason yer protesting me being here is because yer worried ya'll hurt me, ya can just shut the fuck up and deal. i'm tougher than ya give me credit fer. i'm not gonna break if yer a little rough with me." He paused, sighing. "didn't i tell ya before ta stop treating me like glass? i'm here because i want ta be. and yes, i was completely aware of what i was getting inta before i came in here. the pair of ya were lousy teachers and only gave me enough ta know what i was going through at the time, so i did my research."  
  
Blue seemed to relax a bit at that, though he was still frowning. "...promise me you'll get out of here if it gets too much?"  
  
"can't promise that, blue. yer scent has my magic going nearly as haywire as my own heat did. i'll stop ye if i can't handle it, though. i promise," Red replied, smiling. Blue didn't look completely satisfied with that, but he sighed, closing his eyes. He was well aware that he wasn't going to win this.  
  
"Okay, you win. Get some rest. You're gonna need it," he mumbled, sitting up. He'd let Red get some sleep before he lost control again.  
  
"mm. hey, blue?" Blue canted his head, looking back at Red. "heh. if i'm still asleep when ya start losing it again... ya've got my consent ta do whatever ya need ta," he said before rolling over and letting out a sigh as he fell asleep.  
  
Blue could only stare at Red's back and groan at that.


	2. Chapter 2

**Summary for the Chapter:**

> _Please_ note the tags for this. This chapter warranted a couple new ones. I understand my weird kink isn't everyone's weird kink, and then things get a little messy in this chapter. I really don't want to upset anyone.

**Notes for the Chapter:**

> okay, i didn't... actually do any real editing this time. it'll probably be done with little word later, once this is completed.

Blue paced restlessly back and forth. He'd managed to get a little bit of rest, but Red's building scent from his pseudo-heat had knocked him straight out of his doze and caused his own heat to flare up again. This was why he absolutely hated having his heat set in completely. He wished he'd asked Red to sleep with him, but he couldn't do that. They weren't even anywhere near official, considering Red hadn't expressed wanting to be with them in a romantic sense. That he was here, willing to help Blue out with his heat despite that was... really nice, honestly.  
  
The shorter skeleton sighed, raking a hand over his skull as he glanced at the clock. Three hours. He'd managed three hours so far. How Red was still sleeping was beyond him. He could see the crimson glow from Red's pussy, even across the room as he was. Did he wear Red out that much? Another gust of a sigh escaped Blue as he stared at Red thoughtfully. He _did_ have permission... and as long as he was gentle, Red probably wouldn't have any issues...  
  
He swallowed, and slowly crossed the room back over to his bed. He didn't know how much longer he could control himself, given how wonderful Red smelled, but he crept closer anyway. One hand lifted to ghost up Red's femur as he settled behind the tailed skeleton. He shifted his hand, dragging his fingers gently across Red's pelvis before his fingers found his cunt.  
  
A feeling of nervous excitement built up in Blue as he decided to challenge himself. How much could he do to Red without waking him up? Humming quietly, he slowly rubbed at Red's slit, pausing to thumb at his clit every few strokes. The action earned him quiet, breathy moans and hips pressing into his hand. He stopped, letting Red settle again before resuming. He repeated the actions over and over until Red was dripping, translucent red magic staining his fingers. Letting out a breathy moan of his own, Blue slipped in fingers inside his sleeping friend, slowly pumping them in and out, pausing every time it looked like Red might be stirring.  
  
Finally, he'd had enough. Groaning under his breath, he withdrew his hand, rubbing his dick with fluid soaked fingers for a moment before shifting forward a bit more. Carefully, he moved Red's tail out of the way, then slowly shifted until he was laying down behind his friend, nearly cuddled up to his back. Red let out a quiet sound in his sleep, shifting back happily into Blue's warmth, unknowingly grinding into Blue's erection causing the smaller to let out a pleasured hiss.  
  
Unable to hold back anymore, Blue slowly hooked his arm under Red's femur, lifting his leg until he had unhindered access to his cunt. He dragged his dick through Red's slick, pausing a moment once again as Red looked like he was about to wake up. As soon as he was settled once again, Blue grinned and lined up, slowly pushing his dick into Red's waiting cunt. Both of them moaned long and low at the slow drag of Blue's entrance. Once he was fully hilted, Blue paused to let Red adjust, glancing at his face.  
  
Somehow, Red had slept through that, a clear testament to how relaxed Red had become since arriving over a year previous. "Stars..." Blue muttered, settling to nuzzle the back of Red's skull. He then slowly began to move, pulling out only to thrust back in with shallow, gentle movements. It wasn't nearly enough, but Blue still had enough control left that he could still keep to his wish of not waking Red up.  
  
Each movement had Red letting out tiny moans and gasps as pleasure built up in his body. And then Blue jabbed in harder than before, and Red jerked awake with a gasped cry, arching against Blue. "nn, fuck..." he groaned sleepily, pressing back against Blue's hips needily.  
  
Blue let out a breathy laugh. "Ah, sorry. I didn't mean to wake you," he whispered, then licked the back of Red's neck, drawing another moan from the taller skeleton.  
  
"shit, _ah, nnnnn..._ it's okay. i was-" Red paused, moaning as Blue decided to pick up the pace, "expecting it," he managed, whimpering. _"fuck, blue, harder!"_ Blue let out a moan of his own at that and complied, slowing down a bit, but thrusting hard enough to jab against the back of Red's magic in long, hard thrusts, causing him to cry out and writhe. Blue, in response, clamped his teeth down hard on Red's shoulder. "AH! BLUE!" Red screamed, arching and pressing in closer as he was driven over the edge. Red's walls squeezing around him sent Blue over as well, and he moaned around his mouthful as he emptied himself inside Red. The fanged skeleton whined quietly at the feeling, his walls pulsing around the still hard cock buried inside him.  
  
When Blue pulled out, Red whined again but shifted until he could sit up. Curious, Blue watched as Red eyed his cock, making a considering expression. "hey, blue?" he asked, and Blue made an inquisitive sound. "there's something i... uh... wanted to try..." Red paused, face flushing and twisting in embarrassment as he looked away and rubbed the back of his skull in a nervous gesture.  
  
Blue tilted his head as he pushed himself up, watching as Red seemed to battle with himself for a moment before clearing his throat. "What is it?" Blue finally asked when Red didn't continue.  
  
"uh... um... eye socket..." Red muttered, blushing bright enough to cast a dim glow on the area around him. Blue blinked uncomprehendingly. As he realized Blue didn't get it, Red shifted nervously and cleared his throat again. "i, uh... want ya ta try fucking my eye socket..." he murmured, not looking at Blue.  
  
"..." Blue stared silently, wondering if Red was joking... but he didn't seem to be. "...okay. But if it looks like you're in any pain, I'm going to stop," Blue conceded, then stood up on the bed. Red looked nervous still, but that was tinged with a bit of excitement and he shifted so that he was facing Blue, raising up onto his knees so that his sockets were even with Blue's cock.  
  
It was Blue's turn to be nervous as he took his dick in hand, tracing the tip along the lower edge of Red's right socket, leaving a smear of purple from their mixed fluids along the bone. In response to the sensation, that eyelight went out, leaving Red looking up at Blue with only one hazy red eyelight. It was strange, but not unappealing. Carefully, Blue shifted until he was nudging the head of his cock into Red's socket. The magic that made up Red's eyes tingled against him in an extremely pleasant way, drawing a shaky moan from him. At the same time, Red's hands shot up to wrap around Blue's femurs, clutching at him as he gasped at the intrusion. " _Nn..._ are you okay, Red?" Blue forced himself to ask, doing his best to hold himself back from just thrusting in. It felt so good it was hard to resist.  
  
"ah... y-yeah. it... feels weird, but not... not bad," Red replied, voice wavering strangely. He didn't look like he was in pain, though, so Blue took his word for it, slowly pushing in further until Red was gasping, a trail of drool escaping his open jaw. His hands were twitching against Blue's legs, phalanges reflexively tightening and loosening in almost random intervals. He pushed forward a little more until his dick was fully sheathed inside Red's socket before focusing on his face. His jaw hung open, tongue lolling out slightly. His remaining eyelight was rolled back in his head as he panted roughly, and at first, Blue thought that he might be hurting Red, but then he noticed the fact that Red's eyelight was shaped into a hazy heart.  
  
"You... does that really feel good?" Blue asked, cupping Red's face with one hand and petting his skull with the other. Red didn't answer, apparently beyond the ability to speak, but his heart-shaped eyelight blew wider in response and he let out a breathy whimper. "Stars, Red," Blue muttered, awestruck. He then shook his head and shifted his hands until he was holding Red's skull steady. "Going to start now," he warned, then slowly pulled back until only the tip was inside before pushing back in just as slowly. Red whined, clutching Blue's legs harder.  
  
Soon enough, Blue started speeding up, unable to help himself. The magic of Red's socket felt too good against him. As he built up speed, Red seemed to find his voice, though everything that came out of his mouth was babbled nonsense and Blue didn't even try to make any sense of it. All that mattered was that both of them were still enjoying it.  
  
All too soon, Blue felt like he was about to cum. Not wanting to cum in Red's socket, something deep in the back of his mind telling him it would be a terrible idea, he pulled out. Red whined, phalanges tightening around Blue's legs, a desperate look on his face. "Open your mouth wider," Blue murmured, tone not quite commanding, but barely a request, either. None the less, Red complied, jaw falling open further for Blue to thrust inside. Red moaned around his cock, his throat automatically forming for him to swallow around it, causing Blue to groan as he came hard down Red's throat.  
  
Once he was done and he'd pulled back, he released Red's skull. He wasn't expecting Red to collapse sideways, trembling. "...Red?" he questioned, sinking to his knees next to his friend, putting a hand on his humerus. Red twitched, moaning softly, though he didn't move otherwise aside from the continued trembling. "Red, look at me," he ordered, concern forcing his heat back a little. Red's head turned slightly, and Blue frowned, noting that Red's eyelight was still out, the remaining still blown wide in a hazy heart shape. He wasn't focusing very well, if at all.  
  
Blue muttered a soft curse under his breath, a tiny little flicker of fear for his friend starting to surface. Using a small burst of blue magic, he dragged the bag Red had brought with him over to the bed and dug through it. Water, mustard, spider cider, as well as several easy to consume snack items... Red had come well prepared at least. He pulled out and uncapped a water bottle, then looped an arm under Red, gently easing the limp skeleton up into a sitting position. Once he had Red upright, he carefully pressed the bottle to his mouth. "Drink, Red," he told him, tipping the bottle. The first little bit of cold liquid leaked from his mouth, but then he seemed to come around a little bit and he gulped greedily at the water, whining faintly every time Blue pulled it back for him to breathe.  
  
By the time the bottle was empty, Red seemed a little more aware, his single eyelight returned to its normal shape, though it was still a little hazy. He hummed softly, nuzzling into Blue's shoulder. Blue wasn't having any of that at the moment though. He took Red's chin, forcing him to meet his gaze. "Red? I need to make sure I didn't hurt you. Can you light your other eye?" Red blinked, but then seemed to focus for a second before it flickered back to life. Blue let out a soft sigh. "You can see okay?" He was met with a nod in reply and frowned, wondering why Red wasn't actually saying anything.  
  
Everything fell silent, Blue pulling Red a little closer to him and petting the slightly taller skeleton's skull in an effort to soothe both of them. He wasn't sure what was going on, but Red's abnormal behaviour had actually done more to diminish his heat than actually having sex had done. He was worried. Red closed his sockets, his trembling beginning to worsen as he turned his skull into Blue's shoulder. Unsure of what to do, the smaller cuddled Red as close as possible before reaching for Red's robe and pulling it around his shoulders.  
  
It wasn't long after that that he felt a wetness against his shoulder. Red's breath hitched, and Blue realized with a start that Red was crying. Why was he crying? Alarm caused him to tense, but he quickly forced himself to relax, petting Red's skull again and rubbing his back gently over the robe while muttering quiet platitudes. It was all he could do while he waited for Red to either calm down or cry himself to sleep. On top of that, he knew he needed to find out what, exactly, prompted this. Was it the socket thing? But Red had asked for that. Had he gone too far? He faintly recalled Red babbling, but he couldn't understand what Red had been saying. Had any of that been his safe word?  
  
...what if it had? A bolt of horror shot down his spine at the thought, terrified that he'd maybe broken Red's trust, and even more terrified that he'd actually hurt Red.  
  
A moment later, he realized with a pang of regret that he'd have to call Papy home. He knew, if he'd harmed Red, his counterpart would need someone else there to help fix this. He couldn't do it himself, as much as he wanted to. If there was nothing actually wrong after all, Papy could use his newly made shortcuts to get back to the city and his convention after a meal and a nap.

**Notes for the Chapter:**

> Red's condition has an explanation, which comes up in the final chapter for this mess.  
> On that note, there's no more sin for this fic. Only fixing shit that's already happened left. Blue's heat is taken care of.


	3. Chapter 3

**Notes for the Chapter:**

> done. not the best, considering i was fighting writer's block at the end, but.... eh. i just want this done and out. haha

Red had fallen into an uneasy sleep after about an hour of crying silently into Blue's shoulder. The last thing he wanted to do was leave Red alone, but he had to call Papy and didn't want to wake Red after he'd finally dozed off.  
  
As carefully as he could, he slipped off the bed, pulled on a long shirt, then grabbed his phone and stepped out into the hall, closing the door most of the way behind him. With a level of dread he wasn't expecting to feel, he dialled his brother's number.  
  
The phone rang three times, then there was a click before Papyrus' voice could be heard over the line, raised a bit to be heard over the noise of many other people talking. _"what's up, bro?"_ he asked, sounding more cheerful than usual. He was clearly having fun... and Blue was about to ruin that.  
  
"...Papy... I... um...."  
  
_"well, that certainly doesn't sound good. hold on, Sans. lemme find somewhere a bit more private,"_ Papyrus said, and Blue just knew his older brother was frowning now. He could hear it in the other's voice.  
  
"...okay," he replied. The line died a moment later, and Blue leaned against the railing, waiting for Papyrus to call him back. Five minutes later, the phone rang in his hand. He didn't even give the ringtone a chance to finish before he was picking up. "Papy?"  
  
_"yeah. okay, bro, explain. what's going on?"_ Papyrus demanded. Aside from the distant sound of traffic, there was silence on the other end. Blue figured he'd probably shortcutted back to the hotel.  
  
Blue was silent for a moment before taking a deep breath. "...I went into heat," he started. There was a sharp intake of breath from Papyrus' side, but other than that, silence. "I wasn't intending on letting Red know, but he found out anyway and decided to help."  
  
_"and you let him?"_ Papyrus asked, though his tone wasn't accusatory. _"we didn't exactly give him a full explanation."_  
  
"No. Not right away, anyway. I blocked him from coming in the first time... but later he used a shortcut... and my control wasn't exactly the best," Blue replied, hesitatingly. "After that first round, I tried to get him to leave, but he got mad about being treated like glass and said he'd done his research." Blue paused, laughing weakly. "He called us lousy teachers."  
  
Papyrus' answering chuckle was short. _"well, not like that's untrue,"_ he commented, then sighed. _"so, you let him stay after that?"_  
  
"...yeah. We rested for a while, then, uh... got back to it. Everything was fine at first, but then he asked me for something specific, and... I was apprehensive about it, but I did it anyway because Red sounded so sure... but I... I think I hurt him," Blue finished, sagging.  
  
It was silent for a moment before Papyrus sighed. _"Sans, I need to know what you two did."_  
  
Blue flinched. "He... he wanted me to fuck his eye socket. I was careful, I swear. I made sure I wasn't hurting him, but it... it felt so good, I... He was babbling, and I couldn't understand what he was saying. What if he wanted me to stop? What if he was saying his safe word? I..." Blue trailed off, biting back a quiet, horrified sob.  
  
_"...Sans? you didn't cum in his socket, did you?"_ Papyrus asked quietly. Blue vigorously shook his head, but then realized that Papyrus couldn't see him.  
  
"No! I... I didn't think that would be a good idea. I finished, uh... in his mouth," he replied quickly. "But when I let him go, he collapsed and was trembling. It took a while to get him to come around. I did what I could to take care of him... but..."  
  
_"okay. I think I have the full picture here. I'm coming home. Get back in there. Don't leave him alone, okay?"_  
  
"...okay, Papy. Thank you... and I'm sorry for ruining your convention..."  
  
_"you and Red are more important than any convention, bro. anyway, I'll be home in about an hour. see you soon, bro."_ With that, the line went dead. Blue sighed and headed back into the room, not feeling any better than he had before. Red was curled up into a ball, trembling in his sleep, and Blue felt a wave of guilt crawl up his spine at the sight. Without another word, he carefully climbed back onto the bed and pulled the covers up over both of them before gently pulling Red close to him. Red uncurled and nuzzled into his chest. Like that, Blue also fell into an uneasy sleep.

\--------------------------------------------

Papyrus sighed deeply as he hung up the phone, beginning to pace. He knew he needed to start working on making his shortcuts back, and that both Sanses needed him there, but he needed to work off some of the restless irritation first. He wasn't annoyed at having his convention disrupted, of course. That was the _last_ thing he was concerned about.  
  
No, he wished Blue had called him to help with his heat. He wished Red's odd little kink had come out at a better time. Like maybe when no one was in heat, for instance. The magic in a skeleton's sockets was exceptionally delicate, given the direct connection to their manalines. Having heat-influenced magic buried in there was dangerous, with the potential to throw the skeleton into shock, which it sounded as if it had. He was just glad that Blue had instinctively known not to cum in Red's socket. Who knew what kind of damage that could have done.  
  
Taking a deep breath and letting it out slowly, he dialled Undyne's number. She answered with an excited, breathless chirp, asking him where he was. She must have been getting to see something good.  
  
"I'm in the hotel room. listen, Undyne, something's happened back home. I'm leaving my stuff in the room, and hopefully, I'll be back before the end of the week, but..." he sighed. "unfortunately, I'm needed and I don't know how long it's going to take to deal with this situation."  
  
_"...oh. Okay, Papyrus. If you aren't back in time, I'll bring your things home! I'll also be sure to take lots of pictures when I can and make notes on anything interesting while you're gone. That way you aren't missing things,"_ Undyne replied, and though she sounded a little bit disappointed, Papyrus smile.  
  
"thanks, 'Dyne. I appreciate it. hopefully, I'll see you back here in a couple days," he replied. She returned his sentiment and they both hung up. With that, he started working on creating a string of shortcuts.  
  
By the time he reached Ebott, Papyrus was already exhausted, and it was with a sense of relief that he was able to reach for an existing shortcut, porting himself directly back home, where he collapsed onto the couch to recover. The house was silent, but when he held his breath and listened closely, he could hear the faint sound of rattling bones, interspersed with the occasional hiccuping sob. Frowning, he forced himself up and into the kitchen where he filled and downed a huge glass of spider cider. That done, he grabbed a bottle of honey and made his way upstairs.  
  
Blue's door was partly open, and he sniffed the air. The faintest scent of fresh berries and cinnamon hit his nose, but the scent was faded. Obviously, Blue's heat had been dealt with, or his overwhelming worry for Red's state had knocked him out of it. Either way, it likely wouldn't be a problem to be dealt with. He sighed silently and pushed the door open to be met with the sight of the two Sanses curled up in bed together, Blue looking sleepy and trying his best to sooth the shivering, sobbing skeleton in his arms.  
  
Just as Blue looked like he'd just woken up, Papyrus wasn't sure Red was even awake and Blue hadn't even noticed him come in, too focused on Red to be paying attention to his surroundings. Quietly, he stepped around so that Blue could see him, and the smallest skeleton offered a shaky, relieved smile. "...Papy..." he whispered, sounding on the verge of tears himself.  
  
"hey, baby bro," he whispered back, canting his voice to a soothing pitch as he sat down on the bed behind Red, then reached out. His hand lightly touched Red's face before he frowned. Red was cool to the touch, almost cold around his sockets. "...fuck, i was afraid of that..." he muttered, then sighed at Blue's alarmed look. "okay, Sans, I'm gonna tell you now that this is _not_ your fault. it's not Red's fault either. unfortunately, Red picked a bad time to let his kink come out," he said, smiling tightly as he reached a little further to pet Blue's skull.  
  
"...what's wrong with him?" Blue asked meekly, head pressing into Papyrus' hand.  
  
"he's in shock. if you hadn't been in heat, the socket thing would have been safe enough as long no one was cumming in there. you were right in your instinct to pull out. the thing is, though, our magic is stronger, more forceful, when heat is applied. the magic in our sockets is the most vulnerable, given that it's directly connected to our manalines," Papyrus explained. Blue whimpered softly, horror written clearly on his face. He opened his mouth to speak, but Papyrus gently shushed him. "yes, you hurt him, but not intentionally. you didn't know, and he likely didn't either. this kind of damage isn't permanent, though. we just need to gently ease him out of it."  
  
"...how?" Blue's eyelights locked on Red, tears gathered in the corners of his sockets, but they weren't falling.  
  
"for starters, feel how cool he is?" Blue nodded. "we need to get him warmed up. you've got the right idea with cuddling, but a warm bath will be a little faster, and will double to get him cleaned up." Papyrus smiled, carefully pulling the blanket back, then scooped up the trembling mass of bones. "c'mon now, Sansy. up you get. we're gonna help him together, yeah?"  
  
"Yeah!" Blue replied excitedly, speaking a little louder than he'd meant to. The volume of his voice caused Red to stir, and he flinched, shrinking down into himself as Red's sockets cracked open.  
  
"whoops. well, we were gonna have to wake him sooner or later, anyway," Papyrus murmured to Blue, then looked down at Red. "hey, Red. Blue and I are gonna take care of you. just relax, okay?" Red didn't react, gaze vacant. Papyrus muttered a curse under his breath, now concerned that the scarred skeleton was worse than he'd thought. He didn't say anything to Blue about it, though, knowing that his brother was already feeling super guilty about the situation as it was. Instead, he led the way to the bathroom and instructed Blue to start the shower and get it warmed up.  
  
As Blue was doing that, Papyrus carefully unwrapped Red, dropping the robe on the floor and tugging him a little closer when Red started shivering harder, barely visible eyelights hazing out further. "Okay, Papy... the shower's warm..." Blue mumbled, and Papyrus thought that if the younger had lips, he'd have been biting them.  
  
"good. get your shirt off and get in. you're gonna hold him while I rinse you both off, okay?" Blue nodded, then stripped and climbed in. Once he was settled on the floor of the tub, Papyrus carefully set Red down, then stripped his hoodie off, dumping it on the counter before reaching for the shower head. The first contact of warm water against him had Red gasping and whining, eyelights focusing a little. "you with us now, Red?" he questioned. Red only whined, shifting under the spray. Papyrus shook his head. That'd be a no. He was only really reacting on some base level. Unsurprising, really.  
  
Once the two smaller skeletons were rinsed, Papyrus plugged the drain and switched the shower to the bath tap. He checked for temperature, then nodded to himself when it was still good. "okay, bro. I want you to make sure he doesn't go under. I'm gonna grab a cloth. I'll be back before the tub is full."  
  
"Okay, Papy," Blue replied, sounding more subdued again as he gently rubbed Red's arms. Once he was sure Blue was actually okay with him going, Papyrus left the bathroom, heading for the closet where they kept the towels and stuff. After pausing a moment in thought, he grabbed the biggest towels they had and shortcutted down to the laundry room. He shoved them all into the dryer with a dryer sheet, started the machine on a quick cycle, then shortcutted back up. Smiling slightly, he grabbed a few cloths, then returned to the bathroom.  
  
He was just in time, too. He closed the door, then turned off the water. Blue had sunk into the warmth of the water, holding Red so that his face was safely above water-level, but everything else was below. Papyrus chuckled at the sight, then dipped a cloth in the water. "Red?" Hazy eyelights flicked to him, and Papyrus smiled a bit more, pleased that Red was responding a bit better now. "I'm gonna put this over your sockets," he told him. Red let his lids fall shut, letting out a quiet sound. Gently, Papyrus rested the warm cloth over Red's sockets, and he let out a pleased hum, somehow sinking more bonelessly against Blue. It wasn't perfect, but it was an improvement for sure, and Papyrus was happy to see it.  
  
"I'm so sorry, Red..." Blue suddenly murmured. Red made a muzzy, questioning sound. "I hurt you. I didn't mean to, but I-" He was cut off as Red sloppily lifted a hand and smacked it weakly against Blue's arms.  
  
"st' tha'..." Red slurred, voice barely audible in the sudden silence of the bathroom. "di'n' hurt m'."  
  
Papyrus chuckled, petting Red's skull gently. He was relieved that Red was talking, even if he wasn't too clear. He'd thought Red was pretty bad off, but maybe he'd just reacted differently than the way he'd been told. Either that or Red was really good at recovering quickly. He'd probably need a lot of help over the next couple days, but that wasn't a big deal.  
  
Blue didn't respond to Red's efforts to reassure him, but Papyrus could tell it was more that he was trying not to cry that caused him to hold his tongue. Red didn't seem too put out by the lack of reply, though, simply letting his hand drop back to the floor of the tub and letting out a quiet humming sound.  
  
While that was going on, Papyrus stripped down, then picked up one of the extra cloths. He then stepped into the bath himself, sinking to his knees so he was straddling the legs of the smaller pair. "Red? I'm gonna wipe you down, okay?" Red nodded vaguely and Papyrus sighed silently before reaching into the water. "I'm gonna have to touch your ribs. I don't think you can do this yourself right now, and I need to make sure everything is okay with the flow of your magic," he warned, and Red whined slightly in response, but he didn't protest otherwise, so Papyrus got to work.  
  
He wet the cloth in the water, then gently pulled Red into his arms to start. The soft, wet cloth was rubbed over the back of his skull, now warmed by the heat of the water, then stroked down his neck and spine. Papyrus rubbed back up his spine, humming soothingly as he worked. He rubbed over Red's shoulder blades and shoulders, one at a time, then handed Red back to Blue, who cuddled him close. Papyrus then shifted his attention to Red's arms, rubbing down along them. Red's phalanges twitched as Papyrus rubbed the cloth between his radius and ulna, then he carefully stroked over each hand bone before switching his attention to the other arm.  
  
By the time he was done both Red's arms, the faint sound of purring filled the bathroom and Papyrus could see the slightest flush of crimson on Red's cheekbones. "okay, Red, i'm going to do your ribs now. I'll try to be quick about it, okay?"  
  
"...'kay..." Red replied quietly, and if it weren't for the fact that he was worried about Red freaking out, Papyrus would have grinned. He'd found nothing wrong so far, and Red sounded a little more coherent now, too. Focusing back on his task, he let his cloth covered hand stroke at Red's ribs, starting with the lower ones, since they were the most likely to cause issues. Red's body seized up and he let out a low whine but didn't try to stop Papyrus. As promised, Papyrus moved on quickly, hand moving up to safer areas on Red's torso and feeling a sense of relief when the scarred skeleton relaxed again.  
  
Papyrus finished as quickly as possible with Red's rib cage, then moved down to his lower spine, checking each bone carefully as he went. He was quick over the bones of Red's pelvis, moving on to his tail, then repeating what he'd done with Red's arms and hands to his legs and feet. When he was done completely, Red was flushed and purring heavily, no signs of distress left from having his ribs touched. When he reached out to touch Red's face, it was still a touch cool-feeling, but he attributed it more to his hand being warmed from the water at this point.  
  
"okay, everything seems fine. how are you feeling, Red?" Papyrus asked. One of Red's hands lifted from the water and sloppily pawed at his own face to tug the cloth off his sockets before opening them. His eyelights were nearly solid dots of crimson in his sockets, though one was slightly hazier than the other. Papyrus figured that was the one that Blue had fucked. Red stared at him for a moment before letting out a soft breath.  
  
"...better," he rasped after a moment, voice distorted slightly by the purring, which he didn't seem able to stop at that moment. Papyrus chuckled.  
  
"okay then. I'm gonna go get the towels and then we can go cuddle up on the couch together," the tallest skeleton replied, reaching out and stroking Red's skull again, then did the same to Blue. Both of them leaned into the brief contact, and then Papyrus stood and stepped out of the tub, grabbing the single towel on the rack to give himself a quick wipe down before shortcutting to the laundry room.  
  
Once there, he pulled the warmed towels out of the dryer and ported back with his armload. Blue had already started draining the tub, and when Papyrus appeared with his armload, he carefully shifted Red until Papyrus could pull him up and wrap him in a warm, fluffy towel. Red didn't fight it, letting out a content sigh and burying his face in the edge of the towel, much to Papyrus' amusement. It was surprisingly cute.  
  
Blue's reaction to the warmed towels was just as cute, the smallest skeleton letting out a contented humming sound as he wrapped the huge towel around himself for a moment. Then he was drying quickly and wrapping a dry towel around Red as best he could. Red purred a bit louder at the added warmth, making Papyrus chuckle.  
  
"okay, you two... how about we go cuddle on the couch and watch TV for a bit?" Papyrus asked, smiling. Red let out a purr distorted sound that could have passed for an agreement, but Papyrus couldn't be sure, seeing as Red just snuggled further into the warm fluff of the towels. Blue nodded, though. "right then. Blue, go get dressed. comfy clothing. grab those fluffy pjs you got Red for gyftmas last year as well, okay?"  
  
"Okay, Papy," Blue replied, then left the bathroom. Papyrus followed him out, heading downstairs. He got Red settled on the couch, then used the extra towel to finish getting Red dried off while the fanged skeleton relaxed into the cushions, content to let Papyrus fuss over him. He didn't think he could effectively move to do anything on his own at that point in time, anyway.  
  
When Blue came down, he was wearing his coziest set of pyjamas, Red's folded set hugged to his chest. "ah, good. just in time," Papyrus said, smiling gently as he carefully pulled the now damp towels away from Red, who whined at the chill of the room against his bare bones. "yeah, yeah, gimme a sec," Papyrus muttered, chuckling as he took the clothing from Blue. Getting the fleece pants on was fairly easy, but the shirt wasn't quite so simple, given Red's limited ability to move on his own.  
  
Red let out a grunt of frustration as he was forced to let Papyrus and Blue wrangle him into his clothing, but being dressed was a relief. He tried to thank them, but his words were once again not coming clearly. Papyrus stroked his skull soothingly, seemingly recognizing the building frustration. "don't push yourself, Red. it's good to see you've recovered enough to be frustrated by this... but your magic isn't going to work well for a bit, and you'll be dealing with periodic disruptions for probably a few days," Papyrus said, then stood, grabbing the blanket and tucking it around the two smaller skeletons on the couch. "I'm gonna go get dressed as well. I'll be back in a couple minutes, then we can order delivery and watch whatever shitty movies we can find."  
  
Red snorted, hazy eyelights tracking Papyrus as he left before darting to the strangely silent Blue. Despite the fact that they were wrapped up together, Blue seemed to be doing his best to keep his distance, an air of guilt radiating off him, regardless of Red's efforts to reassure him in the bath. Red grunted, then shifted as best he could until he managed to flop over across Blue's lap. Blue gave a startled yelp, flailing slightly, and Red let out a satisfied huff as Blue tentatively rested his hand on Red's skull. "b'in' st'pi'. sto'," he muttered brokenly. He hated that his voice didn't want to work right, but he would work with what he had until whatever had gone wrong had healed. At least he knew he was in a safe place where he could recover without being worried about being taken advantage of or being dusted. He trusted these two idiots more than he'd trusted anyone in a long time. It was a strange feeling, but... he was happy.  
  
When Papyrus returned, dressed in the most ridiculous bee and honeycomb-patterned pyjamas Red had ever seen, they cuddled up together on the couch, Red sandwiched warmly between the brothers. They then settled in to watch human TV until they'd all fallen asleep.

\--------------------------------------------

Grillby sighed as he came up to his friend and employee's home. It was late, and honestly, he was exhausted, but he'd promised a burger and fries, and he wasn't one to break his word. He'd just get in, put the takeout bag on the kitchen table, then go home and crash for the night. Quietly, he opened the front door and stepped inside. He wasn't sure what he was expecting, but it wasn't nearly absolute silence. Perhaps the two of them had worn each other out? Likely, actually.  
  
Grillby yawned himself at the thought and carefully toed off his shoes before stepping out of the entrance hall. He wasn't expecting to have to stop short as a wall of bones suddenly shot up in his path. "...uh..." he stated eloquently.  
  
"...Grillby?" That was Papyrus' voice. So did that mean that Red's partner had been Papyrus? Had Red not mentioned that he'd be stopping by to drop off food?  
  
"Yes," the bartender replied. "I came to drop off food for Red. Did he not inform you?" he asked.  
  
"oh. Red knew you were coming?" Papyrus asked, and Grillby made an affirmative sound. The wall of bones vanished in a shimmer of magic, revealing Papyrus standing in front of Red and Blue, both who were fast asleep, despite the noise. Grillby was a little perplexed now, seeing as Red had said one of his roommates was away. "okay. probably a good time to inform you that Red will probably be out of work for an indeterminate amount of time," Papyrus told him, stepping away from the sleeping pair and motioning Grillby to follow him into the kitchen.  
  
Once they were in there, the elemental set down his food package. "I already gave him the week off, considering he informed me he was aiding one of you with a dom heat," Grillby stated, and Papyrus chuckled softly.  
  
"yeah, that'd have been Blue. I was supposed to be away at a convention, but something happened and Blue needed to call me back. Red got hurt, and I'm not sure how long it's going to take him to completely recover. worst case, his magic will be on the fritz for up to a month. best case scenario is a week, but it's hard to tell." Papyrus sighed, shrugging. "at any rate, he'll be on bed rest for at least a week, but he's probably going to be going stir crazy."  
  
Grillby frowned worriedly at the news, wondering just what had happened, but knew it was really none of his business. If Red decided to talk to him about it, he'd listen, but he'd keep his non-existent nose out of it unless it was brought up. "His job will be waiting for him once he is recovered," he said, and Papyrus practically beamed at him. "Regardless of our personal relationship, I want my employees in peak condition, and I'm not going to fire someone just because they are sick or injured. I'll text to check up on him tomorrow. Make sure he gets this?" He lightly tapped the takeout bag, and Papyrus glanced at it, then nodded.  
  
"sure thing," he said, then sighed with a smile. "I'm glad Red managed to make a friend like you, Grillby," the tall skeleton added. Grillby smiled back.  
  
"I'm grateful to be able to call him my friend as well," he replied, then stepped back. "I'll leave you to get some sleep. Good night, Papyrus. Take care." Papyrus nodded, and with that, Grillby left, worried about Red, but glad that he had the brothers to look after him.

**Notes for the Chapter:**

> okay, so i'm gonna explain this in case it wasn't all too clear. basically, Red went into what could basically be called medical shock for a monster. not as dangerous as it is in a human, but still plenty bad if you don't know how to help the affected monster.
> 
> the cause was having volatile heat-affected magic interacting directly with the vulnerable magic of his socket. if Blue hadn't been in heat when that kink came up, things would have been fine as long as he didn't cum while inside. (a little is fine. pre-cum won't do much aside from maybe disrupt the skeleton's sight for a bit).
> 
> the effects of shock in a monster can range depending on the severity and type of monster. Red exhibited some serious symptoms, making Papyrus think he was worse off than he actually was, so of course, it was a relief that he came around as quickly as he did.
> 
> shock in a monster, especially ones like the skeletons, can cause disruptions in their magic for a few days, even after they've recovered, so it isn't wise to leave a monster alone until the disruptions have ceased, and it's better to have them on bed rest for a few days to completely recover.
> 
> there are still issues to deal with, but between a guilty Blue and an emotionally stunted Red, it, unfortunately, gets brushed off and pushed away for the most part. Red pulls away from the swapbros a little, and they don't push him. Blue thinks he's wrecked any chances of them being more than friends, but of course, we know that isn't the case.
> 
> it winds up coming up to a head later, after they are finally all together romantically, but the blow-up is surprisingly a small pop, rather than a huge boom and gets settled easily enough. :)


End file.
